#45771: C++ 解答 ez
c84327515@gmail.com
(Neil Lin)
int main(){
long long int a =0,b=0,sum=0;
cin >> a >> b;
if(a<b){
int tempa = a;
a = b;
b = tempa;
}
for(int i = b;i<=a;i++){
if(i%2 == 0){
sum +=i;
}
}
cout << sum;
}